fix(orderBy): ensure correct ordering with arrays of objects and no predicate

Closes angular#11866

Author: petebacondarwin

src/ng/filter/orderBy.js

@@ -212,7 +212,7 @@ function orderByFilter($parse) {
   };
 
   function processPredicates(sortPredicate, reverseOrder) {
-    var reverseOrder = reverseOrder ? -1 : 1;
+    reverseOrder = reverseOrder ? -1 : 1;
     return sortPredicate.map(function(predicate) {
       var descending = 1, get = identity;
 
@@ -246,33 +246,27 @@ function orderByFilter($parse) {
     }
   }
 
-  function objectToString(value) {
+  function objectValue(value, index) {
     if (typeof value.valueOf === 'function') {
       value = value.valueOf();
       if (isPrimitive(value)) return value;
     }
-    if (typeof value.toString === 'function') {
+    if (hasCustomToString(value)) {
       value = value.toString();
       if (isPrimitive(value)) return value;
     }
-    return '';
+    return index;
   }
 
   function getPredicateValue(value, index) {
     var type = typeof value;
     if (value === null) {
-      type = 'null';
+      type = 'string';
+      value = 'null';
     } else if (type === 'string') {
       value = value.toLowerCase();
     } else if (type === 'object') {
-      value = objectToString(value);
-
-      // If the object is a POJO then it doesn't really have a well defined ordering
-      // To allow us to reverse the order of these objects, we artificially use its current
-      // index in the collection as its value
-      if (value === '[object Object]') {
-        value = index;
-      }
+      value = objectValue(value, index);
     }
     return { value: value, type: type };
   }

test/ng/filter/orderBySpec.js

@@ -23,7 +23,7 @@ describe('Filter: orderBy', function() {
     });
 
 
-    it('shouldSortArrayInReverse', function() {
+    it('should reverse collection if `reverseOrder` param is truthy', function() {
       expect(orderBy([{a:15}, {a:2}], 'a', true)).toEqualData([{a:15}, {a:2}]);
       expect(orderBy([{a:15}, {a:2}], 'a', "T")).toEqualData([{a:15}, {a:2}]);
       expect(orderBy([{a:15}, {a:2}], 'a', "reverse")).toEqualData([{a:15}, {a:2}]);
@@ -178,12 +178,17 @@ describe('Filter: orderBy', function() {
         null
       ];
       expect(orderBy(array)).toEqualData([
-        null,
-        null,
         { id: 2 },
-        { id: 3 }
+        { id: 3 },
+        null,
+        null
       ]);
     });
+
+
+    it('should sort array of arrays as Array.prototype.sort', function() {
+      expect(orderBy([ ['one'], ['two'], ['three'] ])).toEqualData([ ['one'], ['three'], ['two'] ]);
+    });
   });
 
 
@@ -321,10 +326,10 @@ describe('Filter: orderBy', function() {
       null
       ];
       expect(orderBy(array)).toEqualData([
-        null,
-        null,
         { id: 2 },
-        { id: 3 }
+        { id: 3 },
+        null,
+        null
       ]);
     });
   });